The straight poop on snowmobiling is that it's stressful to wolves and elk.

Such are the implications of fecal analyses undertaken by Professor Rolf Peterson, of Michigan Tech's School of Forest Resources and Environmental Science, and other researchers in Yellowstone, Isle Royale National Park and Voyageurs National Park, in Minnesota. However, Peterson suspects, snowmobiles are the least of a typical wolf's worries.

Scientists compared the hormone levels of wolves in Isle Royale, where there are no snowmobiles, to those of wolves in Voyageurs, where there is snowmobiling aplenty. Consistently, the Voyageurs wolves exhibited levels of stress hormones.

In addition, the scientists noted another direct relationship between snowmobiles and stress. When snowmobile use tumbled 37 percent in Voyageurs between the winters of 1999 and 2000, fecal stress hormone levels also dropped in the park's wolf population--by 37 percent.

Researchers also found that stress hormones in elk living in Yellowstone National Park fluctuated weekly, rising and falling in direct correlation with snowmobile activity.

"Those are pretty compelling data, but they're hard to interpret," Peterson said. "Does snowmobiling matter to elk or wolf populations, or to individuals, for that matter? Probably not." The availability of food is a far more compelling issue to wolves, he said. "And for elk, probably what counts is surviving the winter, when they are most vulnerable to wolves."

Such studies are made possible by a relatively new research technique. Fecal analysis is providing extensive information about animal populations without traumatizing the individuals.

"We're using animal droppings in a wide variety of ways we never dreamed of," Peterson said. "We're just completing a two-year study of wolf droppings, and it looks like we'll be able to characterize each wolf using fecal DNA. We can track an individual for their entire life, and it's completely non-invasive." Researchers can also test the cows' fecal pellets to determine if they are pregnant.

Scientists are already using a related technique, urinalysis, to indicate a moose's physical condition. "If an animal isn't getting enough to eat, it burns muscle, which shows up as urea in their urine," Peterson said.

Without asking the animals directly, it's probably fair to say they'd prefer this kind of information gathering to the traditional alternative: being shot with a tranquilizer gun and poked with a needle to draw blood.

Peterson's research linking stress hormones in moose and elk with snowmobile activity was published in the journal Conservation Biology in 2001. The coauthors are Scott Creel and Robert Garrott, faculty members at Montana State University; graduate students A. Hardy and Jennifer Sands of Michigan State University; and Jennifer Fox, a graduate student at Michigan Tech.